1. Homeostasis: Regulation and Control
Chapter 8

2. Key words…
Homeostasis
Stimuli
Receptors
Chemoreceptors
Mechanoreceptors
Photoreceptors
Thermoreceptors
Pain receptors
Interstitial fluid

3. Homeostasis
How the body maintains a stable internal environment / keeps the body within tolerable limits despite external changes

4. Detecting Stimuli (p212-213)
Production of signal
Detection of signal
Transfer of signal to target
Response to signal by target
Switching off signal once it has been responded to
Your notes: answer these questions in full sentences. You can edit the slides, type them on word or write it down.
Where can signals come from? Give three examples
What is a stimulus? Write down a definition of this word and give examples
What are receptors? Write down a definition
What are the five main types of receptor? What do these receptors specifically do?

5. Signals from the external and internal environments
Exteroreceptors
Located at or near the external surface of the body.
Sensitive to stimuli outside the body.
Monitor the external environment.
Hearing, vision, smell, taste, touch, pressure, vibration, temperature, and pain. (know examples!)

6. Signals from the external and internal environments
Interoreceptors
Located in blood vessels, visceral organs, muscles, and the nervous system.
Monitor the internal environment.
Usually not consciously perceived; increase in carbon dioxide levels or decrease in pH levels can be detected by interoreceptors

8. You should have read pages 212 – 214. If not, do it NOW!
Then answer questions on page 214.
Yes, all of the questions!
Don’t make me bite you. I can bite through bone, face tumour or not!

9. Key words…
Homeostasis
Stimuli
Receptors
Chemoreceptors
Mechanoreceptors
Photoreceptors
Thermoreceptors
Pain receptors
Interstitial fluid
Do you know these words? No? You should !
Make flash cards or a glossary to help you remember them. They are important!! DON’T MAKE ME BITE YOU!

10. The Nervous System

11. Key words…
Central nervous system
Peripheral nervous system
Sensory neurons
Motor neurons
Interneurons
Effectors
Axon
Myelin sheath
Node (of Ranvier)
Somatic nervous system
Autonomic nervous system

12. Fast control: the nervous system
Read pages 214 – 217 carefully
Copy diagram 8.5b on page 215 (FYI visceral means subconscious/automatic division of the nervous system)
Copy diagram 8.6 on page 217

13. Fast control: the nervous system
Still a bit confused about the divisions of the nervous system?
Check out this short clip to help you go through it. Gotta love YouTube!

14. Activity Go to this link and read pages 1 -2
oussystemrev1.shtml
It is important that you know the different parts of a neuron and can identify them in diagrams. Draw a diagram to help you remember the different parts.

15. You should have read pages 214 – 217. If not, do it NOW!
Notes
You should have read pages 214 – If not, do it NOW!
Then answer questions on page 217 – these will be your notes on this section so do a good job!

16. Mini Review Complete page 92 of your WACE Study guide
You can make electronic flash cards on word by downloading a template ( cards.html ) or just write directly into the book
Use all your resources to make sure you get the answer right

17. Slow control: the endocrine system
Hormones are chemical substances such as proteins, fatty substances, steroids and amino acids
In vertebrates they are secreted directly into the bloodstream from ductless glands
Hormones target and activate specific organs/receptors to cause an effect

18. Is it just me or are this guy’s lips creeping you out a bit?!
Activity:
Copy and complete the table on page 218 – you can incorporate this into a poster using page 219 or make flash cards or just copy the information
You MUST know these examples and exactly what they do for your exam

19. Why do cells and organisms need to respond?
Development, Growth and Reproduction
Zygotes constantly change, genes become switched on/off, cells programmed to die (apoptosis) and differentiate to become more specialised
Certain processes occur due to changes in the internal and external environments

20. Why do cells and organisms need to respond?
Hormones
Responding to changes and correcting changes is an essential role to maintain levels within the body between tolerable limits
E.g. pH, CO2 concentration, H+ ion concentration and blood glucose concentrations (know these examples inside and out!)
Being able to respond to changes in the external environment while maintaining a stable internal environment is essential for life

21. Then answer questions on page 220. Yes, all of the questions!
So by now you know I want you to have read the pages I told you to read…
Then answer questions on page 220.
Yes, all of the questions!
I know what I’m talking about here – I haven’t evolved in millions of years so I’m the boss. And I can totally bite you.